To assess driver risk and to change driving behaviour, insurance companies have started using telematics data. Current deployments use one of the following em bedded-hardware-based methods:                1. A “deep install” black box professionally installed in a vehicle that tracks the vehicle's position and acceleration, or        2. An on-board diagnostic (OBD-II) device that connects to the vehicle and acquires information from it.        
Because of the high capital and/or operational costs of these hardware-based options, some companies have brought to market a pure smartphone solution recently. This solution requires no black box or OBD hardware device. The advantage of a smartphone-based solution is substantially lower cost compared to hardware alternatives, provided the challenges around data accuracy can be solved. Previous work has shown how to achieve accurate map-based telematics using personal mobile devices for mileage and trajectory estimation (U.S. Pat. No. 8,457,880) and estimation of longitudinal/lateral acceleration and associated events (U.S. patent application Ser. No. 13/832,456 and PCT Application Number: PCT/US14/30174).
A pure smartphone solution, however, does not robustly achieve the following desired properties:                1. Reliable vehicle identification and monitoring only when the user is in a pre-specified set of vehicles.        2. Crash/impact detection.        3. Exact times of vehicle movement.        4. Accurate estimation of acceleration when the user is moving the phone.        5. Working when the user has uninstalled the application, or has not brought the phone into the vehicle.        6. Better estimations of determining when the cell phone is being utilised while driving for calling or texting or accessing chat applications.        7. A precise determination of whether the smartphone logging data belongs to the driver or to a passenger.        
Accordingly, there exists a need for an improved system and method for obtaining vehicle telematics data.